(b)
[mid-19C] (UK Und.) a small gang who mask the activities of a pickpocket by surrounding the victim.

(c)
[late 19C+] (Aus.) a criminal gang, a gang of tramps; a prison work gang; thus upper-ten push, upper-class criminals and prisoners, also a tramp gang; pushism, the world of such gangs; pushite, a gang member.

(d)
[late 19C+] (US/Aus.) a crowd, thence a clique, a set, among the most celebrated of which was the Sydney Push, or Sydney University Libertarian Society of the early 1960s; thus pushite, a member of a gang or ‘crowd’.

(e)
[1900s-30s] (Aus./US) a family.

(f) (US) a street fight between gangs.

3.
[late 19C+] constr. with the, an act of ejection, dismissal.

(a) dismissal from a job; usu. as get/give the push v., to be dismissed, to dismiss; also of a lover.